Patinated Brass Sinumbra Lamp

FINE PATINATED BRASS SINUMBRA LAMP
Birmingham, England, 1825-1835

The engraved glass shade above a doughnut-shaped oil font above an air intake vent in the form of a foliate capital, raised on a tapering column, above a wider cylinder on a square plinth base on four pad feet.
H: 19.5”, with glass shade: 26”
Condition: Excellent, Electrified.
Sinumbra lamps use Argand burners patented in England by Ami Argand in 1784 and differ from Argand lamps only in the design of the oil font, which is in the form of a flatted doughnut encircling the burner rather than off to one side, allowing light to stream directly out and down through the hole onto a table without the font blocking light and casting a shadow, hence sin-umbra, “without shade/shadow.” This design was patented in England by Samuel Parker in 1820. Parker called it a “shadowless” lamp.

Geneva-born philosopher and inventor Francois-Pierre-Ami Argand (1750-1803), finally received a British patent for his lamps developed a few years earlier in Paris on March 15th, 1784 (patent no. 1425). His revolutionary invention which promised "a lamp that is so constructed to produce neither smoak [sic.] nor smell, and to give considerably more light than any lamp hitherto known" consisted of a tubular wick held between metal tubes, a rack and pinion wick riser assembly and a tall, narrow chimney that fit closely around the wick causing air to be drawn up through the center of the flame as well as around its outside creating more thorough combustion. It was designed to burn rapeseed (colza) and whale oil, issuing from an oil reserve or “font” positioned so that the oil would flow from the force of gravity to the burner.